智利南部的最后一个冰川-全新世过渡期
K D Bennett1, S G Haberle, S H Lumley
1Quaternary Geology, Department of Earth Sciences, Uppsala University, Villavägen 16, S-752 36 Uppsala, Sweden. Keith.Bennett@geo.uu.se
概括
北大西洋的年轻德里亚斯冷却事件不是一个全球现象. 来自智利南部的新证据表明,这种冷却是区域性的,只影响北大西洋地区.
科学领域:
- 古气候学 古气候学
- 四分学科学 四分学科学
- 海洋学 海洋学 海洋学
背景情况:
- 最后一个冰川结束时,北大西洋出现了显著的变暖.
- 这种变暖被新干旱时代 (YDC) 间断,这是冰川活动恢复的时期.
- YDC冷却的全球性或区域性仍然是古气候学中的一个关键问题.
研究的目的:
- 调查年轻德里亚斯冷却事件是全球现象还是仅限于北大西洋地区.
- 在YDC期间重建南半球古气候.
主要方法:
- 对时间,沉积物和古生态记录的分析.
- 来自智利南部海洋小湖的沉积物核心分析.
主要成果:
- 来自智利南部的沉积物记录显示,在新干旱时代 (Younger Dryas chronozone) 中没有冷却的证据.
- 这表明南太平洋表面水域缺乏显著的冷却.
结论:
- 新德里亚斯冷却事件很可能是一个区域现象,主要影响北大西洋.
- 这些发现挑战了对YDC的全球解释,并支持以北大西洋为中心的机制.
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